Provided by: tigervnc-common_1.12.0+dfsg-4ubuntu0.22.04.1_amd64 
NAME
tigervnc.conf - configuration files for Virtual Network Computing
SYNOPSIS
$variable = "someValue";
$variable = "someValue";
$variable .= "someValue";
$variable = $var1 . $var2;
DESCRIPTION
This man page describes the syntax and options of the three configuration files loaded by
tigervncserver(1), the free X server for Virtual Network Computing (VNC). These configuration files can
be used to change the behavior of the server at startup time, although for all values suitable inbuilt
defaults are preset.
First, /etc/tigervnc/vncserver-config-defaults is read specifying the system defaults. Then,
tigervncserver(1) will proceed and read $HOME/.vnc/tigervnc.conf, a file that can be changed on a per-
user base. The options in this file will override the system defaults. Next, command-line options
overwrite both the system defaults and the settings in $HOME/.vnc/tigervnc.conf. Finally, the
configuration file /etc/tigervnc/vncserver-config-mandatory is parsed. If this file exists and defines
options to be passed to Xtigervnc, they will override any of the same options defined in a user's
$HOME/.vnc/tigervnc.conf as well as options given via the command line. This file offers a mechanism to
establish some basic form of system-wide policy.
WARNING! There is nothing stopping users from constructing their own start script that calls Xtigervnc
directly to bypass any options defined in /etc/tigervnc/vncserver-config-mandatory.
EXAMPLES
The system configuration file /etc/tigervnc/vncserver-config-defaults should come with the Debian package
tigervnc-standalone-server. This file serves as an example for the user file $HOME/.vnc/tigervnc.conf.
The system configuration file is pretty self-descriptive, and this document will mainly repeat the
information that already can be found there.
OVERVIEW
The file is in perl(1) syntax, although only variable assignment is allowed for your safety and
convenience. But there still a variety of possibilities to set the string variables.
All variable names are prefixed by `$'. You can assign a string to a variable using the `=' operator, and
you can append a string to a variable using the `.=' operator. You can concatenate two strings using the
`.' operator. You can substitute variables even inside quotes. You can access the environment variables
using the notation $ENV{VARIABLE}.
You can unset a variable by assigning undef to it. Use this to return the state of the variable from
`set' to `use default'.
You must end a line with a semicolon.
OPTIONS
The options are given with their default value if this is known.
$fontPath = "<font_dir>,<font_dir>,..."
Should be a comma separated list of fonts to be added to the font path. If not specified, the
default will apply.
$PAMService = "tigervnc";
This parameter specifies the PAM service used for plain password authentication if one of the
security types Plain, TLSPlain, or X509Plain is used. If /etc/pam.d/vnc is not present, then
tigervncserver(1) expects to use the tigervnc PAM service to authenticate the passwords of users
when any of the *Plain security types are used. Note that the tigervnc-common package provides
the PAM service configuration file /etc/pam.d/tigervnc. Otherwise, if /etc/pam.d/vnc is present,
then the vnc PAM service will be used.
$sslAutoGenCertCommand = "openssl req
-newkey ec:/etc/tigervnc/openssl-ecparams.pem
-x509 -days 2190 -nodes";
The command specified by the $sslAutoGenCertCommand parameter is used to auto generate the
certificate for the -X509Cert and -X509Key options of Xtigervnc(1). The configuration for
openssl(1SSL) is taken from /etc/tigervnc/openssl.cnf where we substitute @HostName@ by the fully
qualified domain name of the host.
$vncUserDir = "$ENV{HOME}/.vnc";
Contains the filename for the log files directory of Xtigervnc (the server) and the viewers that
are connected to it.
$vncPasswdFile = $vncUserDir . "/passwd";
Contains the filename of the password file for Xtigervnc. This file is only used for the security
types VncAuth, TLSVnc, and X509Vnc.
$vncStartup = "/etc/X11/Xtigervnc-session";
Points to a script that will be started at the very beginning when neither $vncUserDir/Xtigervnc-
session nor $vncUserDir/xstartup is present. If $vncUserDir/Xtigervnc-session is present, it will
be used. Otherwise, we try $vncUserDir/xstartup. If this is also absent, then we use the
$vncStartup script. If $vncStartup is specified in $vncUserDir/tigervnc.conf, then this script is
used unconditionally. That is without checking for the presence of $vncUserDir/Xtigervnc-session
or $vncUserDir/xstartup.
$session = undef;
This option can be used to control which X session type will be started. This should match one of
the files in /usr/share/xsessions. For example, if there is a file called gnome.desktop, then
$session = "gnome" would start this X session. The command to start the session is passed to the
$vncStartup script. If this is not specified, then /etc/X11/Xtigervnc-session will start the
session specified by /usr/bin/x-session-manager.
$xauthorityFile = "$ENV{HOME}/.Xauthority";
Specifies the path to the X authority file that should be used by your Xtigervnc server.
$desktopName = "${HOSTFQDN}:nn ($ENV{LOGNAME})";
Should be set to the default name of the desktop. This can be changed at the command line with
-desktop.
$geometry = "<width>x<height>";
This sets the framebuffer width & height to be used by the Xtigervnc server. On default, 1920x1200
is used. A values for this option as well as the $depth and $pixelformat options can be derived if
the tigervncserver(1) is run in a X session – either $ENV{DISPLAY} or the session given by
$getDefaultFrom – with the -xdisplaydefaults option. The geometry can also be changed at the
commandline with the -geometry option. Otherwise, the fixed defaults given here as well as in the
following two configuration parameter documentations will be used.
$depth = "32";
This sets the framebuffer color depth, i.e., the number of bits per pixel to use. It must be
either 16, 24, or 32.
$pixelformat = "rgb888";
Specifies the pixel format for the Xtigervnc(1) server to use (BGRnnn or RGBnnn). The default for
depth 16 is RGB565 (meaning the most significant five bits represent red, the next six green, and
the least significant five represent blue) and for depth 24 and 32 is RGB888.
$wmDecoration = "8x64";
Sets the adjustment of $geometry to accommodate the window decoration used by the X11 window
manager. This is used to fully display the VNC desktop even if the VNC viewer is not in full
screen mode.
$getDefaultFrom
This option lets you set the display from which you can query the default of the above three
options, if you don't want to start tigervncserver from within a running X server. It will be
added to the call of xdpyinfo. It is useful to get the default from the X server you will run
xtigervncviewer in, because the data has not to be recalculated then.
$getDefaultFrom = "-display localhost:0"; is an example how to do this.
$scrapingGeometry = "<width>x<height>+<xoffset>+<yoffset>";
is only used by the scraping TigerVNC server. It specifies the screen area that will be shown to
VNC clients, e.g., 640x480+320+240. The format is <width>x<height>+<xoffset>+<yoffset>, where `+'
signs can be replaced with `-' signs to specify offsets from the right and/or from the bottom of
the screen. Offsets are optional, +0+0 is assumed by default (top left corner). If the variable is
not defined, full screen is shown to VNC clients (this is the default).
$localhost = "yes";
Should the TigerVNC server only listen on localhost for incoming TigerVNC connections. This is
useful if you use SSH and want to stop non-SSH connections from any other hosts. Hence,
$localhost = "yes" is the default if security types are not specified. In this case, only the
security type VncAuth will be offered. If the security types are specified, either via the option
-SecurityTypes given to tigervncserver(1) or via the $SecurityTypes configuration parameter in
/etc/tigervnc/vncserver-config-defaults or in $HOME/.vnc/tigervnc.conf, then the default depends
on the specified security types. The default will be $localhost = "no" if the specified security
types contain at least one of the TLS* or X509* secutity types and also contain none of the *None
security types. As always, the defaults can be overwritten on the commandline via the -localhost
option or via the $localhost configuration parameter in /etc/tigervnc/vncserver-config-defaults or
in $HOME/.vnc/tigervnc.conf.
$SecurityTypes = "VncAuth"
The $SecurityTypes parameter contains a comma separated list of the default security types the
Xtigervnc server will offer. Available security types are None, VncAuth, Plain, TLSNone, TLSVnc,
TLSPlain, X509None, X509Vnc and X509Plain. The *None security types do not offer any kind of user
authentication for connecting VNC sessions. Hence, combining a *None security type and
$localhost = "no" is a very bad idea. The TLS* and X509* security types do enforce SSL encryption
for data transmission. Hence, combining a TLS* or X509* security type and $localhost = "yes" is a
senseless idea. Thus, in the case of $localhost = "no", the default for $SecurityTypes will be
extended from VncAuth to VncAuth,TLSVnc.
$PlainUsers = "$ENV{LOGNAME}"
The $PlainUsers configuration parameter contains a comma separated list of users that are
authorized to access the VNC server if the security types Plain, TLSPlain, or X509Plain are used
to establish the connection. The password for these users are check by the system via the PAM
service specified via the $PAMService configuration variable or the -PAMService option. On
default, only the user starting the tigervncserver is contained in the list. By specifying *, any
user can authenticate using this security type.
$X509Cert and $X509Key
These two options contain the filenames for a certificate and its key that is used for the
security types X509None, X509Vnc, and X509Plain. If nothing is specified – the default case – then
a self-signed certificate is auto-generated by tigervncserver(1) and stored in
$HOME/.vnc/${HOSTFQDN}-SrvCert.pem and $HOME/.vnc/${HOSTFQDN}-SrvKey.pem, respectively. If
filenames are given for $X509Cert and $X509Key either here or on the commandline via -X509Cert and
-X509Key options, then the auto generation is disabled and the user has to take care that usable
certificates are present.
FILES
/etc/tigervnc/vncserver-config-defaults
The global configuration file specifying the defaults for tigervncserver and x0tigervncserver.
~/.vnc/tigervnc.conf
The user's tigervnc.conf configuration file.
/etc/tigervnc/vncserver-config-mandatory
If this file exists and defines options, they will override any of the same options defined in a
user's tigervnc.conf file or ones given on the command line of the wrapper scripts tigervncserver
and x0tigervncserver. This file offers a mechanism to establish some basic form of system-wide
policy.
WARNING! There is nothing stopping users from constructing their own wrapper script that calls
Xtigervnc or X0tigervnc directly to bypass any options defined in the /etc/tigervnc/vncserver-
config-mandatory configuration file.
SEE ALSO
tigervncconfig(1), tigervncpasswd(1), tigervncserver(1), tigervncsession(8), x0tigervncserver(1),
Xtigervnc(1), X0tigervnc(1), xtigervncviewer(1)
AUTHOR
2022 - Modified for TigerVNC 1.12.0 by Joachim Falk (Joachim.Falk@gmx.de) 2021 - Modified for TigerVNC
1.11.0 by Joachim Falk (Joachim.Falk@gmx.de) 2016 - Modified for TigerVNC 1.7 by Joachim Falk
(Joachim.Falk@gmx.de) 2006 - Modified for vnc 4.1.2 by Joachim Falk (Joachim.Falk@gmx.de) 1998 -
Originally written by Marcus Brinkmann (Marcus.Brinkmann@ruhr-uni-bochum.de) for the Debian GNU/Linux
Distribution.
TigerVNC 1.12.0 Jan 13th, 2022 tigervnc.conf(5x)